Especially in the case of products such as ice cream or alcohol-based granita, where the temperature inside the container is kept at several degrees below zero (for example at about −8° C.), ice may form (owing to condensation) on the outer wall of the container, since the container which is made of transparent plastic does not provide a high degree of heat insulation.
This ice formation results in various drawbacks of both a practical and an aesthetic nature. Machines with improved heat insulation of the container could overcome the problem, but this results in an unacceptable increase in the cost of the container and creates problems of internal visibility which worsen the appearance of the product to the purchaser.
JP11253105 describes a twin-container machine where it is attempted to prevent the formation of ice between the containers due to the fact that the containers are too close to each other. An air flow is therefore emitted from the bottom of the machine upwards into the gap between the containers in order to keep it free from ice. This does not deal with or solve the problem of formation of ice on the free walls of the container and also produces an unacceptable amount of condensate which falls into the air emission slits against the air flow.